http://www.flickr.com/photos/ossy59/sets/72157603469902678/
Many K-mount lenses are listed, from the K/M mount, to the A/F/FA and then to the DA ones. Some 3rd party lenses in K-mount are also listed. The official suggested price per lens is also plotted. But do note that all prices are German ones, nevertheless.
An example screen-shot of the charts is shown below. This one is for the FA*85/1.4:-

My hats off to the guy who compiled the plots! I can see the huge efforts involved (and that he paid)! :-o
Ying · 705 weeks ago
Denis · 704 weeks ago
RiceHigh 110p · 704 weeks ago
ossy59 · 704 weeks ago
@ Ying: 6 years ago you could (I can give you the ebay number).
There have been not a lot of them, but ...
I want to say that I shurely haven´t seen different auctions. But all the points in my charts show one auction, and I have opened all of them to read the description, to have a look at the photos, and to see what kind of seller it is (at the moment I think ~ 15.000)
I know, there is a rest of risc to buy on ebay, but the lenses in my charts are not all found auctions, there are only the lenses I would buy by myself. (The first years the charts only have been was a service for good friends - with a kind of advice like "this one you can buy, it´s ok")
RiceHigh 110p · 704 weeks ago
ossy59 · 704 weeks ago
I try to keep the charts up to date, without too big "time holes" in between.
A lot to do because I am working also on Pentax 645 and Pentax M42 charts ...